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Au-Cu2O supported on reduced graphene oxide was synthesised employing a novel one pot greener approach using sugarcane bagasse waste and Fehling’s solution. It was used for catalytic reduction of nitrophenols under ultrasonic irradiation in water.

The global water situation is highly challenging and requires immediate attention. It is pertinent to explore opportunities in wastewater treatment with an environment friendly route. An efficient method can be explored where biogenic nanoparticles (NPs) synthesized by agricultural waste can further enhance its potential in cleaning the environment. Therefore, a green, surfactant-free and sustainable approach towards the genesis of cuprous oxide (Cu2O) was attempted. Cu2O NPs were synthesized using Fehling’s solution and sugarcane bagasse extract which plays a vital role both as reducing and capping agent. The Cu2O NPs were characterized using Fourier transform infrared and UV–Visible spectroscopy, and their morphology was determined by high-resolution X-ray diffraction, transmission electron microscope and scanning electron microscope analysis. Their optical properties, i.e., band gaps, were calculated, and the catalytic efficiency was studied by carrying out the degradation of organic dyes [methyl orange (MO), methyl blue (MB), methyl red (MR) and Congo red (CR)] present in wastewater via spectrophotometric measurements. Simultaneously, their increasing order of degradation efficiency was found to be MR

Untargeted synthesis leading to the formation of a significant product is a common practice and has been successfully achieved after holistic characterization of the accidentally formed molecule of the trimer of pyrazolone. Its significance was further explored in the pharmaceutical field emphasizing the need for the synthesis and validating the newly established pathways for its synthesis. It was known that pyrazolone exhibit a plethora of applications ranging from catalysis, decolourisation of dyes and metallurgical extractions. Paramount importance has been attributed to pyrazolones in recent years for their broad-spectrum biological activities manifested in their anti-inflammatory, analgesic, anticancer and anti-tubercular functions. In the ongoing research 4,4-Bis-(3-methyl-phenyl-pyrozolin-5-on-4-yl)-3-methyl-1-phenyl-pyrzolin-5-one was synthesized economically and efficiently via a novel one-step bio-catalytic pathway using laccase as a catalyst. To validate the utility of our accidental discovery, we have also calculated its antioxidant activity against ascorbic acid as a standard compound. DPPH and ABTS have been used to study the scavenging of free radicals in-vitro. This is the first report of the enzyme driven synthesis of trimeric form of pyrazolone. These results will emphasise the utilization of pyrazolone trimers as eco-friendly compounds which exhibit a promising natural antioxidant property in physiological environments. An investigatory report is being presented featuring a novel eco-friendly pathway for the synthesis of trimeric of pyrazolone i.e., 4,4-Bis-(3-methyl-phenyl-pyrozolin-5-on-4-yl)-3-methyl-1-phenyl-pyrzolin-5-one. The trimeric form of the molecule possesses spiked antioxidant properties verified by DPPH and ABTS assays. Thus, this work opens new frontiers for further research in this direction.

Adsorption strategies have been used worldwide relentlessly for pollution abatement and remediation. Nanocomposites are the most promising nominees for high degree adsorption processes, and when collaborated with graphene oxide tend to emerge as very efficient candidates for adsorbing various pollutants present in water. The hybrid impact of graphene oxide and material nanocomposites have proved to make large contributions to the adsorption of heavy metals, hazardous organic chemicals (dyes, various VOCs, pesticides, fertilizers, drugs), and other particulate contaminants of water especially industrial wastewater. Graphene oxide contains a cluster of reactive oxygen functional groups anchored on the large surface of the nano-composites which develops remarkable stability and adsorption efficacy in aqueous medium and makes them reusable for multiple number of adsorption-desorption cycles. The current chapter highlights all such adsorption phenomenon for water to decontaminate it and make it salubrious.

When the whole world is reeling under a severe impact of Covid 19, India which is 4 times more populous than US and many other developed nations, is not so severely hit by the epidemic. Despite Indias very low per capita income and poorly ranked healthcare system in the world, it has escaped the brunt of the pandemic. Generally epidemics exhibit exponential growth at the beginning but the initial delay and lower mortality have been ensued from many intriguing possibilities such as high geographical temperatures, high immunity due to poor hygiene, BCG vaccinations and lower average age of the population The ongoing review presents a brief perusal of the probable causes for the initial containment of the pandemic and its potential in India. &nbsp

Researchers have risen to envisage a great deal of potential of nanocomposites (NCs) and foresee a wide range of applications of ternary NCs (TNCs) in particular. The hybrid nanostructures with synergistic impact of metal, metal oxide, carbon containing and polymer nanoparticles (NPs) dispersed on RGO nanosheets, obtained from the convenient protocols (efficient, economical and eco-friendly - E3 approach) along with nontoxic nature have led to a wide range of benefits. Owing to their enormous applications, it is pertinent to review all remedial, sensing, biomedical, energy storage and conversion abilities for traversing furthermore and motivating future researchers. Their consolidated study majorly validates the gigantic role in safeguarding the environment along with their comprehensive efficiency in a spectrum of energy storage and conversion. Moreover, their utilization in sensors also makes them research targets for biomedical scientists exploring clinical investigations. Their significance ensures to construct a link between academic research and environmental sustainability.

Water effluents of various chemical laboratories are expected to consist of wide range of organic waste products whose removal is an arduous task and a serious concern with the objective of eradication of all the pollutants from laboratory waste water has been attempted to modify rice husk’s surface. The efficacy of the designed adsorbent derived using rice husk and its potential in removing the residual dyes has been evaluated in this research. Both raw silica and functionalized silica obtained from the rice husk have proved to possess greater ability than activated charcoal for the biosorption of dyes present in contaminated water. A comparative account of silica, functionalized silica and activated charcoal acting as biosorbent for a common acidic dye: EBT was studied using FT-IR, TEM, IR spectroscopy techniques for their characterization. It was also observed that adsorption tendency of adsorbent was governed by experimental condition directly. The variation in rates and thermodynamic factor also influences the adsorption efficiency. For the removal of EBT from waste water functionalized silica was revealed to be most efficient.

The volumetric analysis allows the quantitative chemical analysis of a solution of the unknown concentration (acid/base) by titrating it with the solution of accurately known concentration (base/acid). For this purpose, chemicals indicators such as phenolphthalein, methyl orange, methyl red, congo red etc. are used. These indicators are expensive and some of them have toxic effects on users and can also cause environmental pollution. Therefore, an attempt has been made to investigate the indicator activity of some of the fruits, vegetables and kitchen spices. The current paper recommends the use of natural indicators such as Curcuma longa (turmeric), Beta vulgaris (beetroot), Citrus × limon (lemon), Citrus reticulata (orange), Citrus limetta (sweet lime), Solanum lycopersicum (tomato), etc. as a strategy for environment remediation, to reduce toxicity and to decrease the respective cost of the synthetic indicators. Various acid-base titrations were carried to ensure a sharp color change with respect to the pH of the medium. The promising results were obtained using comparative studies against standard synthetic indicators. Consequently, the authors suggest that these indicators can be used as pH indicators in the college laboratories for undergraduate courses.

Diorganotin complexes of monoisopropyl and monomethyl nadiate, succinate, and phthalate were synthesized and characterized by elemental analysis, FT-IR, 1H NMR, 13C NMR, and 119Sn NMR spectroscopic techniques. The spectroscopic investigation demonstrated that carboxylate is bidentate in the diorganotin complexes. On the basis of 1 J(119Sn–13C) and 2 J(119Sn–1H) values, C–Sn–C bond angles were also calculated. The newly synthesized complexes were also screened for their antibacterial activities against Gram-positive and Gram-negative pathogenic strains of bacteria.

This article describes the curing behavior of diglycidyl ether of bisphenol-A using Cysteine (A)/ Methionine (B)/Cystine (C)/ mixture of 4,4′-diaminodiphenyl sulfone (DDS) and Cysteine/DDS and Methionine/DDS and Cystine in various molar ratios as curing agent. Differential scanning calorimetry was used to study the cure kinetics by recording the DSC scans at heating rates of 5, 10, 15, and 20°C/min. The peak exotherm temperature was found to be dependent on the heating rate, structure of the amino acids and on the DDS/amino acids molar ratio. A broad exotherm was observed in the temperature range of 150–245°C (EA), 155–240°C (EB), and 190–250°C (EC). Curing of DGEBA with mixture of amino acids and 4, 4′-diaminodiphenyl sulfone (DDS) resulted in a decrease in characteristic curing temperatures. Activation energy of curing reaction is determined in accordance to Ozawa's method and was found to be dependent on the structure of the amino acids and on the ratio of 4,4′-diaminodiphenyl sulfone (DDS) to amino acid. Thermal stability of the isothermally cured resins was evaluated using dynamic thermogravimetry in nitrogen atmosphere. No significant change has been observed in the char yield of all the samples, but it was highest in the system cured using either Cystine alone (EC-1) or a mixture of DDS/Cystine (EC-2, EC-3, and EC-4). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Phytoremediation is described as the treatment of environmental problems through the use of plants that mitigate the same without the need to excavate the contaminated material and dispose it elsewhere. Some plants proved to be popular organism for bio-monitoring to determine and identify the sources of heavy metal soil pollution and their detoxification by phytoextraction techniques. In the present work an attempt has been made to remediate Lead (Pb) and Nickel (Ni) from the polluted soil. Soil and plant (luxuriously growing as hyperaccumulator) samples were collected from the polluted sites to find out the extent of Pb and Ni accumulation in them. We found Saccharum, Brassica juncea, Tamarix and Ricinus as efficient accumulators of heavy metal from the soil. Accumulation of Pd was higher than Ni in soil samples from all the sites. For greenhouse experiment B. juncea was selected for Phytoremediation study. Results of AAS of digested samples of both plants and soils of greenhouse experiments showed that heavy metal content declined in pot soil after plants have been grown and harvested. B. juncea reduced 73.15% Pb and 60.13% Ni from their initial concentration in soil thereby proving itself to be a good accumulator of heavy metals and a remedy for controlling heavy metal soil pollution. Most important in phytoremediation is to use wild plants as accumulators in the greenhouse experiment as it minimizes the chances of biomagnification of heavy metals in food chain.

An increase in the concentrations of heavy metals in the environment from year to year has become a serious environmental concern. Technology development, anthropogenic and industrial activities lead to emission of heavy metals and their accumulation in ecosystem. Heavy metals such as Cadmium (Cd), Cobalt (Co), Lead (Pb) and Mercury (Hg) are toxic to organisms. Due to their non-degradable and persistence in nature, these elements cause serious health problems in human beings and animals through food chain. Therefore, the cleanup of contaminated sites is mandatory for the removal of these potentially damaging substances from soil and water. Although several engineering based methods are already being used to remediate metal contaminated soils but they destroy the biotic components of soil, causes secondary pollution and are expensive to implement. In contrast, Phytoremediation has emerged out as a low cost effective, environment friendly technology in which plants and their associated microbial flora are used to remediate metal ions from polluted areas. In the present study, an attempt has been made to remediate Cadmium concentration from the polluted soil with the help of plant. Cadmium is one of the most toxic elements, which affect the kidney, bones and lungs of human beings. In the present study, soil and plant samples were collected from the different locations containing industrial wastes and tested for cadmium concentration using Atomic Absorption Spectrophotometry (AAS). A significant decline in Cd concentration was observed in pot soil, in which Brassica juncea was grown under green house conditions. Furthermore, higher concentration of Cd concentration in the harvested plant as compared to the seeds, justify the ability of B. juncea to remediate toxic Cd and control soil pollution.

This article describes the synthesis, charac- terization, and thermal properties of nadimides obtained by reacting endo-5-norbornene-2,3-dicarboxylic acid anhy- dride (nadic anhydride) (NA), 4,4 0 -oxodiphthalic anhy- dride (ODA), 1,4,5,8-naphthalene tetra carboxylic dian- hydride (NTDA) in glacial acetic acid/DMF. Structural characterization of the resins was done by elemental analy- sis, IR, 1 H-NMR, and 13 C-NMR. The DSC scan showed the endothermic transition in the temperature range of 120- 2708C. Multistep decomposition was observed in the TG scan of uncured resins in nitrogen atmosphere. Isothermal curing of the resins was done at 250 and 3008C for 1 h in an air atmosphere. These cured resins were stable to (350 6 30)8C and decomposed in a single step above this tem- perature. This may be due to the retro Diels Alder (RDA) reaction. The char yield of the resins increased significantly on curing. The char yield was highest for P-2N resin and this could be due to the presence of rigid skeleton i.e. naphthalene. 2007 Wiley Periodicals, Inc. J Appl Polym Sci 107: 1628-1634, 2008

To determine the efficiency of carbon column for the removal of toxic chemicals from water, the adsorption of phenol in concentration range from 0.600 glt to 1.475 gll was studied on active carbon of 80 CTC grade, 12 X 30 BSS particle size, 1280 m2/g surface area, and of coconut shell origin, under dynamic conditions at space velocity from 0.318 min-' to 4.24 min-' at 25 'C. The carbon column of 100 cm length and 2 cm diameter was found to be removing phenol from the aqueous solution of concentration 1.475 gll up to 84 min at 0.678 min-' space velocity at 5.0 ppm phenol breakthrough concentration. However, no phenol was observed in carbon-treated water after 80 min. The service life of carbon column (100 cm lengthX25 cm diameter) was assessed through the water purification system developed at the Defence Laboratory, Jodhpur and was determined to be 4.095 days with twoas factor of safety for 10 ppm initial concentration of phenol at 0.678 min-' space velocity (corresponding to water flow rate). Effects of carbon bed length, water flow rate, and the phenol concentration were also studied.

Six organotin(IV) complexes of type Me2SnL2, Bu2SnL2, and Ph3SnL [where L = indole–3– butyric acid (1, 2 and 3) or indole–3–propionic acid (4, 5 and 6)] have been synthesized by the reactions of the corresponding diorganotin(IV) oxide and triphenyltin(IV) hydroxide with respective indole–3–butyric acid (IBH) or indole–3–propionic acid (IPH) in the desired molar ratios of 1:2/1:1. All of the compounds have been characterized by elemental analysis, IR, 1H NMR, 13C NMR, and 119Sn NMR spectroscopy. Thermal studies of all synthesized complexes have been carried out using thermogravimetry (TG) technique under a nitrogen atmosphere. The thermal decompositions for compounds Me2SnL2 and Bu2SnL2 occurred in two steps, whereas in compounds Ph3SnL, it exhibited as three steps decomposition and resulted into the formation of pure SnO2. The complexes were also screened against three gram–positive (Staphylococcus aureus, Staphylococcus epidermidis, and Micrococcus luteus) and three gram–negative (Escherichia coli, Pseudomonas aeruginosa, and Enterobacter aerogenes) bacteria using minimum inhibition concentration (MIC) method, and all of these complexes showed significant antibacterial activity. [Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text, tables, and figures.]

The curing behavior of diglycidyl ether of bisphenol-A (DGEBA) with aromatic diamide-diimide-diamines having aryl ether, sulfone and methylene linkages was studied by differential scanning calorimetry (DSC). Nine diamide-diimide-diamines of varying structure were synthesized by reacting 1 mole of dianhydride with 2 moles of L-cysteine (S) in a mixture of acetic acid and pyridine (3:2 V/V) followed by activation with thionyl chloride (SOCl2) and then condensation with excess of diamines. Structural characterization of diamide-diimide-diamines was done by using FTIR, 1H-NMR, 13C-NMR spectroscopy and elemental analysis. The peak exotherm temperature (TP) was lowest in DGEBA cured using EPSM and highest in DGEBA cured using ENSS. Thermal stability of the isothermally cured DGEBA with diamide-diimide-diamines was investigated using dynamic thermogravimetry (TGA) in nitrogen atmosphere, and it was found that NTDA based diamide-diimide-diamines provided good stability to DGEBA. The char yield was highest for resin cured with ENSE which might be due to the presence of more compact structure i.e. naphthalene.